Research On Three-dimensional Surface Morphology Of Laser Micro Processing Based On Wavelet Analysis

With laser micro processing technology in the manufacture of micro-components used more widely, currently researchers mainly focused on improving the processing parameters,processing application specific process requirements of hole and surface.For laser micro processing surface topography is little research,since the evaluation different of the selected plane filtering tools, assessment evaluation base level extraction accuracy in dispute, resulting in assessment systems vary widely, due to the thermal effect of the laser after processing,The material properties of the surface layer changes, surface wear resistance after laser micro processing is not clear, then high-precision micro-components is assessed at the same time is limited to the evaluation of the amplitude parameter, the finished surface has the same surface roughness parameters, do not necessarily have similar topography, How to distinguish with similar roughness parameters, finished surfaces with different morphologies,how to determine the isotropic and anisotropy of the finished surface, as well as the frequency characteristics of the finished surface,how to efficiently process the data,to provide a complete surface assessment software, making three-dimensional surface assessment parameters further promotion and application of such basic research involved relatively less system researchers have focused on the study.Single pit topography laser micro processing were based on the above issues through research, under the description of topographical features single pulse effect provides three main parameters, morphology has heat affected zone and the melt pool, since the laser micro processing surface is made coincident with a certain degree of horizontal and vertical spot superposition surface, a mathematical model of the spot coincidence degree,the establishment of precise contact with the moving speed of the light spot coincides with the worktable feed rate, the use of AFM microscope finished surface for data collection ,on fractal features.typical of the finished surface quantitatively calculation , numerical simulation of the quantitatively various stages surface and the surface of the support rate curves do comparison,research support rates in different regions change the substance of the wear factor,and by types of materials friction and wear test, the wear resistance of the surface after laser micro processing have some knowledge, along with the improvement of laser energy, solidified layer so that the wear resistance of the reinforcing material, and the solidified layer more obvious, the more smooth longer working range.Using wavelet filtering tools laser micro processing surface topography decompose found using the comparison with the original topography reconstruction error value appropriate wavelet basis, the use of the characteristics of digital signals, roughness belong to high-frequency signal transmission characteristics unchanged Under the principle,the removal of the largest high-frequency signal energy to the principle of determining the number of decomposition, extracted wavelet assessment base level, to solve the small number of wavelet selection and decomposition issues, in order to verify the accuracy of the reference plane using the "m" sampling modes and presents the average root mean square deviation of parameters, to distinguish unlike other laser micro processing process unique concave-convex surface characteristics Introduced average Gaussian curvature,The surface fractal dimension of surface detail in the description of distinguishing features is not obvious,proposed surface fractal deviation, can be of different topography and morphology with different surface roughness be a good distinction, for laser micro processing surface one-dimensional power spectral density quantitative analysis of spatial frequency content,and the accumulation of different spatial frequencies of energy, the use of two-dimensional power spectral density of the comparative analysis of the morphology typical process,a two-dimensional power spectrum analysis is a powerful tool for the qualitative determination of the surface of isotropic and anisotropy.Use MATLAB / GUI build up process data evaluation system software from the frequency domain and time domain processing surface of a complete evaluation, covering a large number of research results.